The present invention relates to chemical dispensers and, more particularly, to chemical dispensers for use in flush type toilets.
Hygienic considerations and the formation of unattractive discoloration within toilet bowls have given rise to a major industry, which industry has produced and continues to develop products in an attempt to satisfy the hygienic requirements and eliminate the discoloration. A general solution to these problems revolves around a chemical dispenser disposed within the water tank of the toilet. The dispenser emits a predetermined amount of chemical into the water tank, which chemical, during the water flushing cycle, rinses the toilet bowl.
All toilet water tanks incorporate at least some metallic components and older water tanks have almost exclusively metallic operating elements. The use of any metallic materials within the water tank necessarily precludes the dispensation therein of any chemicals which might oxidize or otherwise chemically react with the metallic elements. Therefore, the highly efficient disinfectants which incorporate chlorine cannot be dispensed into the water tank. Similarily, chemicals having an acidic PH factor and which would alleviate discoloration of the toilet bowl by preventing metallic oxide build up on the surface thereof cannot be dispensed into the water tank. Thus, the type and nature of chemicals dispensible by water tank dispensers is limited to other than the optimum choices.
The prior art chemical dispensing apparatus usually employed one of two types of mechanisms: a float valve operated mechanism for dispensing a predetermined quantity of chemical into the toilet tank in response to the cyclical water discharge; or, a pressure responsive mechanism for regulating the amount of chemical dispensed in compliance with the degree of pressure change.
Although the amount of water within a water tank is intended to be uniformly consistent after each fill cycle, some variation does occur because of varying water pressure, sticking water valves, etc. Similarly, the water tank does not always drain completely and more or less water may remain therein after each cycle. These variations in the amount of water discharged affect the concentration of dispensed chemicals and, hence, alter the effectiveness of the chemicals.
To overcome the necessity for dispensing chemicals into the toilet tank, various suspended devices have been mounted within the toilet bowl itself. Devices of this type have generally received limited acceptance for home use in that they impede periodic cleaning of the bowl and are often disturbed or dislodged during normal use of the toilet.